Re: setting up foreign keys

Sort of on topic, how many foreign keys in a single table is good v.
bad? I realize it's relative to the tables the FK's reference so here's
an example:

Table A: 300 rows
Table B: 15,000,000 rows
Table C: 100,000 rows
Table E: 38 rows
Table F: 9 rows
Table G: is partitioned on the FK from Table A and has a FK column for
each of the above tables

I'm in the process of normalizing the database and have a schema like
this in mind. Works wonderfully for SELECT's but haven't gotten the
data import process down just yet so I haven't had a chance to put it
through it's paces. Depending on the performance of INSERT, UPDATE, and
COPY I may drop the FK constraints since my app could enforce the FK
checks.

TIA.

Greg

> -----Original Message-----
> From: pgsql-performance-owner(at)postgresql(dot)org
> [mailto:pgsql-performance-owner(at)postgresql(dot)org] On Behalf Of Chris
> Sent: Thursday, August 10, 2006 6:36 PM
> To: Merlin Moncure
> Cc: Sue Fitt; pgsql-performance(at)postgresql(dot)org
> Subject: Re: [PERFORM] setting up foreign keys
>
> Merlin Moncure wrote:
> > On 8/10/06, Chris <dmagick(at)gmail(dot)com> wrote:
> >> Sue Fitt wrote:
> >> > Thanks Chris and Chris, you've solved it.
> >> >
> >> > I had a gui open that connects to the database. It was doing
> >> > nothing (and not preventing me adding to or altering
> headwords_core
> >> > via psql), but having closed it the table is instantly
> created. Weird.
> >> >
> >> > BTW, referencing the same column twice is deliberate, it's a
> >> > cross-reference.
> >>
> >> The same column and the same table?
> >>
> >> Same column different table I could understand but not the same
> >> column & table ;)
> >
> > create table color(color text);
> >
> > create table person(eye_color text references color(color),
> hair_color
> > text references color(color));
>
> lol. Good point :)
>
> *back to the hidey hole!*
>
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